Erich Hückel (9.08.1896-16.02.1980) was a German theoretical physicist. He was born in Berlin — Charlottenburg. In 1921 he received the degree of Doctor of Philosophy at the University of Göttingen, where in 1922 he was assistant to M. Born; in 1922—25 he worked at the Zurich Polytechnic, from 1930 he was Privatdozent at the Technical University in Stuttgart, and in 1937—62 professor at the University of Marburg.
His work was in the field of quantum theory, quantum chemistry and electrochemistry. In 1922, together with Born, he studied the rotation-vibration spectra of polyatomic molecules. In 1923, with P. Debye, he developed the theory of strong electrolytes, which explains the form of the dependence of the activity coefficient on concentration — the logarithm of the activity coefficient is proportional to the square root of the concentration (the Debye—Hückel theory). He constructed the quantum theory of double bonds (1930) and the quantum theory of benzene rings (1931—32). He applied the method of molecular orbitals to the study of aromatic and unsaturated compounds, developed the theory of unsaturated compounds, predicted the stability of aromatic compounds and gave a rule (the Hückel rule).
A member of the Leopoldina Academy (1966), of the International Academy of Quantum Molecular Science (1968) and of the Royal Society. The O. Hahn Prize (1965).